This invention relates in general to an assembly that can be used for adjusting a variety of components of a chair and more particularly to an adjustable four plate assembly that can adjust various components of a chair and more specifically the armrest of a chair in isolated motions or motions in conjunction with one another, namely, side to side in a lateral movement, pivoting in an arc like motion and sliding forwards and backwards in a longitudinal movement.
The ability to adjust a chair to provide maximum comfort for the user is a primary concern for the ergonomics discipline. As users and chairs come in all shapes and sizes, the ability to accommodate each user to each chair has become important to the comfort and productivity of the user. This issue is of particular importance for those individuals that use computers and/or spend considerable lengths of time sitting. Therefore adjustable armrests, backs, the height of the chair and various other positions have been addressed in a wide variety of inventions to improve on comfort and accommodate the user""s desires.
For example, U.S. Pat. No. 5,971,484 issued on Oct. 26, 1999 to Lambert et al relates to an adjustable armrest for chairs that includes a support plate that is rotatable about the main pivot to adjust the angular orientation of the armrest construction and is laterally movable along continuously parallel positions to adjust the width of the armrest construction relative to the chair.
Tornero is the owner of U.S. Pat. No. 5,586,811 which, was issued on Dec. 24, 1996 and this patent relates to an adjustment device for selectively positioning a structural member such as an office chair arm relative to the seat. The device includes a planar support member and a retaining member which are joined to encase a bearing through which a slidable structural member is adjusted. The device allows for laterally positioning the arms of a chair to accommodate users of different body widths.
Piretti is the owner of U.S. Pat. No. 6,095,598 which, was issued on Aug. 1, 2000, and this patent relates to a chair armrest having pivotable front portion, and a chair including this armrest. Specifically the device includes a front portion being rotatable between two operative positions which are angularly spaced from each other by about 180 degrees, allowing for the front portion to be offset laterally inwardly with respect to a rear portion.
Bujaaryn is the owner of U.S. Pat. No. 5,984,408 which, was issued on Nov. 16, 1999 and this patent relates to compound lever and armrest mounting assemblies, namely an armrest support that is pivotally attached to the mounting assembly and includes a linkage for indexing movements of the armrest support relative to motion of the position of an upper rail relative to a lower rail, so that the motion of the upper rail relative to the lower rail produces a corresponding tilt of the armrest support
Urso is the owner of U.S. Pat. No. 5,755,650 which was issued on May 26, 1998 and this patent relates to a home and office health and fitness chair that includes a bracket that allows for pivotal movement of the arm support about a horizontal axis. A linear slide having an upper and lower portion is fixed to the bracket to allow linear movement.
Thus an adjustable assembly which can adjust various components of a chair and more specifically the armrest of the chair in isolated motions or motions in conjunction with one another, namely, side to side, pivoting and sliding front to back, is desirable.
An object of one aspect of the present invention is to provide an improved chair adjustment mechanism and more specifically an adjustable four plate assembly for a chair that provides for a variety of adjustments such as angular pivot adjustment, width adjustment and depth adjustment.
In accordance with one aspect of the present invention there is provided an adjustable four plate assembly for a chair including a first plate having a top surface and a bottom surface, a second plate having a top surface and a bottom surface adapted to receive the top surface of the first plate so as to allow for the pivoting of said second plate from side to side. A third plate having a top surface and a bottom surface adapted to receive the top surface of the second plate so as to allow for the sliding of the third plate from side to side. A fourth plate having a top surface and a bottom surface adapted to receive the top surface of the third plate so as to allow for the sliding of the fourth plate forwards and backwards. The adjustable four plate assembly allows for the second plate, the third plate and the fourth plate to move independently of one another and or in combination with one another.
Conveniently, the adjustable four plate assembly includes specific hardware to allow for maximum adjustment range for each of the motions, as well as providing an individual position for each of the motions within the ranges.
Advantages of the present invention include the ability to move the four plate assembly in a variety of ways, namely sliding forward and backward, sliding side to side or angular pivoting side to side. These motions or positions may be conducted in isolation or in conjunction with one another.
The adjustable four plate assembly may be used in adjusting an arm rest of a chair, or adapted for use in the back of a chair or a lumbar support. Furthermore the present invention requires fewer components to achieve the desired movements and does not require covers to hide the components. All of the components of the invention are contained within the adjustable four plate assembly and are not exposed when the arm rest is moved to extreme positions. Finally the components of the present invention are configured in such a way that a portion of the entire assembly is housed with in the arm rest reducing the size and bulk of the visible plates between the armrest support and the armrest.